Automatic railway safety control



L. F. HELLMANN AND W. W. BAXTER.

AUTOMATIC RAILWAY SAFETY CONTRDL.

APPLICATION FILED my 14. 1919.

1,340,861 Patented y 18, 1920.

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LUI F. HELLMANN AND WILLIAM W.

PATENT OFFICE.

BAXTER, OF INDIANAPOLIS, INDIANA,

ASSIGNORS TO .AIR BRAKE SAFETY APPLIANCE 00., OF INDIANAPOLIS,

INDIANA, A CORPORATION.

AUTOMATIGBAILWAY SAFETY CONTROL.

Specification of Letters Batent.

Patented May 18, 1920.

Application filed May 14, 1919. Serial No. 297,107.

To all whom, it may concern Be it known that we,LU1 F. HELLMANN andVVILLIAM W. BAXTER, citizens of the United States, residin at 154:9Leonard street and 128 South 'fraub street, respectively, in the city ofIndianapolis, county of Marion, and State of Indiana, have inventedcertain new and useful improvements in automatic railway safety controlto be used on and in connection with trains operated by electricity,steam, or other means ofmotive force.

()ur invention relates more especially to those modes of conveyance andtransportation which operate by means of some power over a line ofrails, and which are equipped, or are to be equipped, with air brakes,or other pressure types of brakes, of that type most commonly known asthe air brake systern.

The object of our invention is to produce a means for eliminating thehuman factor from the control of the train during such times when thetrain shall have become dangerous, and a menace to public safety, byvirtue of some failure of the air supply system which will cause theressure in said air supply system to become angerously low, or failentirely.

A further object of our invention is to produce a means forautomatically taking over the control of the train when, throughcarelessness or neglect of the driver, the train shall have become amenace to public safety.

A further object of our invention is to produce a means which willprevent the operation of the train until the brake system shall be in anoperative and safe condition.

A further object of our invention is to produce a positive means foraccomplishing the objects above set forth.

A further object of our invention is to produce a means, which, iftampered with, will prevent the operation of the train.

A further object of our invention is to produce a means, whereinthefailure of any vital part thereof will cause thetrainto stop, andwill prevent further operation of the train until the defect has beenremedied, or proper safety precautions taken.

With these objects in view, our invention consists generally, of anautomatic brake control valve placed in connection with the hand controlvalve; an electro-magnetic means for operating said valve; anelectropneunlatic switch for controlling the operation of said valve,for controlling the predetermined limits of the permissable varia tionof the brake pressure, and for operating the motive power cut-outmagnet; and an electro-magnetically operated circuit breaker or throttlevalve or other means for controlling motive force to the train.

ur invention further consists of various details of construction andarrangement of parts, all as will be fully described hereinafter andparticularly pointed out in our claims.

Our invention will be more readily understood by reference to theaccompanying drawings which form a part of this specification, and inwhich,

Figure 1 represents a general diagrammatical view of the arrangement,giving the layout of the piping and the wiring diagram, and shows theapplication and connection of the automatic control valve with the caror train piping. 1

Fig. 2 represents a sectional and detailed view of the automatic controlvalve.

Again referring to the drawings, 1 indicates the trolley wire or othersource of electric power or current, 2 indicates the rails or oppositesource of power. 3 indicates the drivers brake, or hand control, valve 4indicates an auxiliary circuit breaker. 5 indicates the magnet whichtrips the circuit breaker 4, when the current fails. Magnet 5 can beplaced in conjunction with the regular circuit breaker and stillaccomplish the desired results.

6 indicates the trolley or other means for taking up the electriccurrent, 7 indicates the wire carrying said current to the circuitbreakers; 9 indicates the wire carrying said current from the circuitbreaker 4 to the motors and other devices which may be upon the carertrain.

10 indicates the automatic control valve, Ilindicates the wire carryingthe current from the track or other means or source of power, into thecontact devices of the control valve.

12' indicates the wire carrying the current :from the contact devicesofthe control valve into the magnet of the same, while 13 indicates thewire from the magnet of the control valve to the trip magnet of thecircuit breaker. V

14 indicates the tank or storage reservoir, for brake pressure and 15indicates the pipe line carrying this pressure from the tank 14 to thehand control valve 3.

16 indicates the brake cylinder and 17 indicates the pipe carrying thepressure between the control valve 10 andthe brake cylinder 16, while 18indicates the pipe between the hand control valve 3 and the automaticcontrol valve 10.

19 indicates the pipe carrying the pressure between the main reservoirline 15 and the automatic control valve 10, and 20 the release oratmospheric pressure line.

21 indicates the magnet of the automatic control valve 10, 22 indicatesthe solenoid plunger for the same, 23 indicates the piston rod, 24 thepiston rod packing nut and 25 the piston rod packing.

26 indicates the main pressure space, 27 indicates the contact pressurecylinder, 28 indicates the port between the pressure space 26 and thecontact cylinder 27, 29 indicates the contact piston, 30 the contactpiston release spring, 31 the release spring adjusting nut, 32 thecontact surface, 33 the contact surface insulation and 34 the contactpiston rod.

35 indicates the contact springs, 36 the contact holding screws, 37 thecontact insulation and 38 the cover.

39 indicates the main cylinder, 40 the main piston, 41 the main pistonpacking, 42 the main spring, 43 the main spring adjusting nut, 44 thecylinder head, 45 indicates the port to pipe 18, and 46 indicates theport to pipe 17.

The drawings which form a part of this specification are diagrammaticalonly and are notscaled working drawings. The sizes and pressures of thevarious springs shown and the proportions between the various pistonareas shall be so designed and proportioned that all will properlyfunction to give the working and results as described throughout thisspecification.

The operation of the automatic railway safet control is as follows,-

It is assumed that the train is in an operative or safe condition. Whenthis condition exists there is a certain predetermined pressure in themain reservoir 14. This pressure is then flowing through the pipes 15and 19 into the chamber 26 of the automatic control valve 10.

There is also a. regular electrical pressure in the trolley wire 1 andthe track 2.

The pressure in the chamber 26 is communicated to the cylinder 27through the port 28. When this pressure is at its proper predeterminedlimit,it forces the piston 29,

the piston rod 34, the contact surface 32 and the contact surfaceinsulation 33 outward so that the contact surface 32 permits a free flowof electrical current between the 0011- tacts 35, thereby permitting afree flow of current from the track 2, through contacts 35, throughcontact surface 32, through wire 1.2, through magnet 21, through wire13, through circuit breaker magnet 5, into wire 9, through the circuitbreaker 4, after said circuit breaker has been thrown in, through thewire 7, through the trolley pole 6, and into the trolley wire 1. It willbe noted that the track 2 is assumed as being the positive side of adirect current system. In case the trolley wire 1 is the positive sideof the said system the current would flow from the trolley wire 1 to thetrack 2 through the same wires, breakers, magnets and contacts, exceptthat it would flow in a reverse direction. In alternating currentsystems no direction of flow could be established.

Circuit breaker 4 is now thrown in by hand and a flow of current passesfrom the track 2 to the trolley wire 1, through the magnets 21 and 5.This flow causes magnet 5 to hold circuit breaker 4 in a closedposition, and permits the normal operation of the train and the regularpump which keeps up the pressure in the tank 14.

Simultaneously the plunger 22 of the magnet 21 is drawn in and thepiston 40 and the piston packing 41 are drawn in by the piston rod 23,thereby closing the chamber 26 from the cylinder 42, and thereby causingport 45 and port 46 to open into the cylinder 42 as shown, in directcommunication with each other, and this said opening permits a free flowof pressure between pipes 17 and 18, and thereby permits regular ormanual operation of the braking system by means of the engineers valve3, or regular, safe operation of the train.

When through accident, carelessness or neglect, the pressure in the tank14 is reduced to a predetermined limit, this limit to be sufficientlyhigh to make it effective in the operation of the brakes the pressure inthe chamber 26, and consequently in the cylinder 27 is correspondinglydecreased and the pressure of the spring 30 against the piston 29 causesthis piston to move inward, thereby causing the contact surface 32 towithdraw from and break connections with the contacts 35, which breaksthe flow of current between the wires 11 and 12.

This demagnetizes the magnet 21, releases the plunger 22 and permits theremaining pressure in the chamber 26 to force the piston 40 outwarduntil it has passed over the port 46 and has established a freecommunication between the chamber 26 and the port 46: A free flow of theremaining pressure is now established from reservoir 14 through pipe 15and 19 into the brake cylinder 16 through the pipe 17. This remainingpressure is suiiicient to fully set the brakes and stop the train.

Simultaneous to the operation of the auto matic brake control valve, themagnet 5 becomes demagnetized and permits the circuit breaker 4 to breakthe current passing between the wires 7 and 9. This operation closes oilthe motive power of the train and prevents the further operationthereof.

Before the train can again be operated it is necessary for the driver tohold the circuit breaker 4 in by hand, until a sufficient pres sure hasbeen reestablished to close the circuit between the wires 11 and 12, atwhich time the starting position will again be reestablished.

From the foregoing it will be seen that to make our invention adaptablefor steam or other railways, it will merely be necessary to replace thecircuit breaker 4 with a. motive power throttle control valve, whichwould be automatically operated by the magnet 5, in which eventthe'current for the operation of our devices would come from someinternal source.

Having described our invention, what we claim as new and desire to coverby Letters Patent is,

1. An automatic safety control comprised of a means for automaticallyapplying brakes, said means comprised of a means for maintaining anormal passage from the operators brake control valve to the brakemechanism in combination with a means for automatically closing thepassage from the operators brake control valve to the brake mechanism, ameans for opening a passage from the air supply line to the brakemechanism, said means arranged to automaticaliy operate when thepressure in the air supply system shall have fallen to a predeterminedpressure, and a means for shutting off the motive power, said meansarranged to operate automatically when the pressure in the air supplysystem shall have fallen to a pre determined pressure, substantially asdescribed.

2. In a combination comprising an automatic control system, a means formaintaining a normal free passage through the air line from theoperators brake control valve to the brake mechanism in combination witha means for automatically closing the passage to the operators brakecontrol valve and opening a passage from the air supply line to thebrake mechanism, arranged to function whenever the air pressure in theair supply system shall have fallen to a predetermined pressure, and ameans for shutting off the motive power, said means being operatgd bythe means which causes the brakes to function whenever the pressure inthe air supply system shall have fallen to a predetermined pressure,substantially as described.

3. An automatic control, comprised of a means for applying brakes, saidmeans to consist of a means for maintaining a normal passage from theoperators brake control valve to the brake cylinder, a means foractuating the brake applying mechanism when the brake pressure shallhave fallen to a predetermined pressure, a means for opening a secondarypassage from the source of air supply to the brake cylinder, and a meansfor shutting off the motive power, said means consisting of a means foropening the circuit controlled by the means for actuating the brakeapplying mechanism when the brake pressure shall have fallen to apredetermined pressure, substantially as described.

a. An automatic control valve comprised of a means for maintaining anormal passage from the operators brake control valve to the brakecylinder in combination with a means for closing said normal passage andopening up a secondary passage from the source of air supply to thebrake cylinder, and an electro-magnet for operating said means forclosing the normal passage and opening up the secondary passage, saidelectro-magnet to be actuated by the fall of pressure in the air supplysystem to a predetermined pressure, substantially as de-' scribed.

5. An automatic control valve comprised of a means for maintaining anormal passage from the operators brake control valve to the brakecylinder in combination with a means for closing said normal passage andopening up a secondary passage from the source of air supply to thebrake cylinder, an e1ectro-magnet for operating said means for closingthe normal passage and opening up the secondary passage, and a means forenergizing and deenergizing said electromagnet, said means forenergizing and deenergizing said electro-magnet to be actuated by thefall of pressure in the air supply system to a predetermined pressure,substantially as described.

In testimony whereof we have signed our names to this specification inthe presence of two subscribing witnesses.

LUI F. HELLMANN. W. W. BAXTER. \Vitnesses E. J. PORTER, H. E. WEBER.

